Device and method for sorting plies

ABSTRACT

A ply sorting device is disclosed, comprising a picker and a buffer. The picker is arranged to pick planar plies of cut fiber material and move them to the buffer. The buffer comprises a plurality of substantially planar supports each arranged to receive phes from the picker and to support the plies in planar orientation. The planar supports are movably arranged relative to each other to receive the plies. In addition, a method of sorting plies of differing geometry is disclosed. Planar plies of cut fiber material are picked and moved to supports of a buffer where plies are received in a planar orientation, and supports are moved relative to each other to receive the plies.

RELATED APPLICATIONS

This application is a 35 U.S.C. § 371 national phase application ofPCT/NL2018/050397 (WO 2018/236212), filed on Jun. 19, 2018, entitled“Device and Method for Sorting Plies”, which application claims thepriority to Netherlands Application No. 2019094, filed Jun. 19, 2017,which is incorporated herein by reference in its entirety.

The invention generally relates to sorting of plies, and in particularto sorting of cut plies of fiber material.

Such plies are generally known, and are used to manufacture fiberreinforced composite products. Such plies are typically cut from a sheetof fiber material. The fiber material may be dry, but may also beimpregnated, e.g. with a thermosetting resin or a thermoplasticmaterial. The plies may comprise a backing material.

The plies themselves are unfinished products: they are to be placed inlayers in a mold. Typically, the plies that are to be placed in the moldhave differing orientations and may have differing geometries. The pliesare placed in a prescribed order in the mold. Individual plies typicallyhave a specific location in the mold, and an orientation of its fibersto optimize the strength of the product. The layered plies in the moldare then subjected to heat and/or pressure to form a laminated product,in particular a high strength, low weight product for use in demandingapplications, e.g. structural parts for use in aerospace.

Plies of different geometries may together make up a set to be used formolding of a composite product. A set of plies may typically compriseplies of different size and shape, but may comprise or even consist ofplies of the same geometry. A composite product may itself be comprisedof several sets of plies, the sets together forming a kit for theproduct. Fiber reinforced composite products as used in the aerospaceindustry may be composed of dozens or even hundreds of plies that needto be processed in a tightly controlled environment for qualityassurance.

The fiber material is usually supplied on very long sheets that arerolled up on a roll. To optimize the use of the sheet material, theplies of several sets may be nested as cutouts in a sheet. These setsmay each be identical, but may also differ. For example, different setscorresponding to smaller and larger products may be nested on the sheetto optimize use of the sheet material.

Due to the nesting, the plies are typically not in an order so thatsubsequent plies can be picked from the sheet to form a set. Forexample, a ply for a first set may come first, followed by another plyfor a second set.

In order to accommodate for this, the plies are typically manuallyremoved from the sheet, and placed on a large buffering table. Thesurface of the buffering table comprises several support areas, whereplies are laid down. In these support areas, the plies corresponding toa set are collected in a stack.

However, the manual handing of the plies is labor intensive, and timeconsuming. Even with careful manual handling, errors in handling and inparticular in sorting may not always be avoided. Tight quality controlis required, which in itself increases costs and processing time. Inaddition, the large buffering table takes up floor space, which incombination with a required clean environment is expensive.

Due to limited shelf life of the resin as unfinished product, the pliesshould further be processed to products fairly quickly. Prolongedstorage of plies or sets of plies is better avoided.

Also, as they are unfinished, the plies as cut from the sheet of fibermaterial are delicate, and should be handled with utmost care to preventcontamination, and loss of integrity.

With manual handling, loss of integrity can not always be ruled out, andon the buffering table the plies are easily contaminated—especiallybecause they often reside on the buffering table longer than isdesirable.

The invention aims to alleviate at least some of the above mentioneddisadvantages. In particular, the invention aims to provide a device andmethod for sorting plies, with which the cost efficiency of handling ofthe plies can be increased, and/or with which the quality of the pliescan be improved. In particular, the invention aims to reduce handlingtime, to reduce the floor space needed for sorting, to improve thecontrol of integrity of the plies, and/or to prevent contamination.

Thereto, the invention provides for a ply sorting device, comprising apicker and a buffer, wherein the picker is arranged to pick planar pliesof cut fiber material and move them to the buffer, and wherein thebuffer comprises a plurality of substantially planar supports eacharranged to receive plies from the picker and to support the plies inplanar orientation, wherein the planar supports are movably arrangedrelative to each other to receive the plies.

By using a device with a picker to pick and move the plies to thesupports, the integrity of the plies can be controlled better, and lossof integrity may be prevented. In particular, the plies can be moved insubstantially planar orientation, which reduces the chance of damage.Also, the plies can be picked and moved to the support for the set in asingle operation. Such single operation further saves handling time, andreduces the chance of damage. By arranging the planar supports to bemovable relative to each other for receiving the plies, the supports maymove toward the picker, and thus further save handling time. Also, byarranging the planar supports to be movable, the supports may be movedfrom a storage position in which they have a covering arrangement thatprevents receiving of plies, to a receiving position that allowsreceiving of plies. Such covering arrangement saves space, and preventscontamination due to sheltering.

By interspacing the supports perpendicular to their plane, the coveringarrangement may be facilitated. The supports may be arranged to bemovable along their plane and/or movable perpendicular to their plane.

By embodying the supports as shelves, a compact construction may beobtained. A shelf may include a plurality of supports, e.g. adjacentsupports in a plane. Elegantly, the shelves are embodied as, or mayinclude trays. This way, the plies may be supported in a protectedtrough. The trays may be removable from the shelves. The trays and/orthe shelves may be removable from the buffer. This way, a stack of pliesmay be loaded to or offloaded from the buffer with a tray or shelf.

By arranging the shelves above each other in a column, a particularlycompact construction may be obtained. The column may then offer ashelter. The shelves may each be slidably mounted to a frametransversely to a longitudinal direction of the shelves.

Elegantly, the shelves may be arranged to slide outwards of the column,preferably at opposite sides of the column. The shelves may then slideout from a storage position in the column in which they overlap and aresheltered, to a receiving position adjacent the column in which they areaccessible for the picker and are free to receive plies.

As an alternative, the shelves may be liftably mounted to a frametransversely to a longitudinal direction of the shelves. The shelves maythen be liftably mounted with a variable interspace to accommodate thepicker between shelves.

In particular, the shelves of the column may be arranged to be movedrelative to each other in groups. This way, adjacent shelves of thecolumn may be parted, and provided with an interspace to accommodate thepicker, in particular the gripper head of the picker, between shelves.Elegantly, the shelves of the column may be moved up or down as a singlegroup, so that the shelves to be parted are positioned at a fixed heightbefore parting. Regardless of their position in the column, the shelvescan be made available for the picker to access at a single heightposition relative to e.g. the floor. This way, the construction of thegripper may be simplified as it may travel back and forth in the sameplane, and the speed of operation may be increased.

One side of the column facing the picker may be part of a stay out zonethat during operation is not accessible to humans, and wherein anopposite side of the column facing away from the picker is part of asafe zone that during operation is accessible to humans. This way, thebuffer may be implemented in a flexible production cell easilyaccessible to a robot, and yet be easily and safely accessible to humansas well.

The ply sorting device may further comprise a substantially planarpickup plane. The pickup plane may be a moving belt surface associatedwith the output of a sheet cutter. The pickup plane may be part of asheet cutter, e.g. part of an output conveyor of the cutter. The pickupplane may also be part of a secondary conveyor, that in use connects toan output conveyor of the cutter. The pickup plane may, however, also bepart of a stationary surface, e.g. a sorting table, or a support planeexternal or internal to the buffer. The pickup plane may also be part ofa bin that holds a stack of plies, e.g. plies that have manually beenremoved as cutouts from the skeleton of a cut sheet. The buffer andpicker may then form a stand alone unit.

The picker may comprise a plurality of gripper organs arranged in agripper plane, e.g. on a gripper head. A detection plane may be arrangedparallel to the pickup plane, to detect material extending between thepickup plane and the gripper plane.

The ply sorting device may be operatively associated with a sheet cutterarranged to cut plies from a sheet, e.g. via a common control unit orvia a communication module. This way, the sorting device may becontrolled using data from the cutter, e.g. operational data or cuttingfile data. Also, the cutter may be controlled using data from thesorting device, e.g. data on ply occupancy and/or availability at thesupports.

The invention further relates to a method of sorting plies of differinggeometry, wherein planar plies of cut fiber material are picked andmoved to supports of a buffer where plies are received in a planarorientation, wherein supports are moved relative to each other toreceive the plies. The supports may be moved along their plane and/orperpendicular to their plane. Elegantly, the supports may be moved apartin an upward or downward lifting operation to receive plies.

In the method, the plies may be picked by the picker as cutouts from askeleton of a cut sheet, in particular a moving sheet. Such moving sheetmay be provided by a conveyor belt of a cutter, or a feeder table. Thishas the advantage that the location and orientation of the plies in thesheet may be derived from the cutting data. The plies may, however, alsobe picked by the picker from a stationary location, e.g. a feed table orother support location, and may have e.g. been removed from the skeletonof a cut sheet in a previous operation, e.g. a manual operation. In suchcase, the picker may be provided with a vision system to assess theplies, e.g. to identify the plies and/or to assess the orientation. Insuch method a feed stream of plies may be sorted and placed in a buffer.

Using the method, plies may be sorted in a way that they are received bythe supports in a stack, e.g. a stack of plies corresponding to aproduct, or a stack of plies that are the same or similar. Plies mayalso be received by the supports adjacent to each other, e.g. as singleplies only or as adjacent stacks.

Using the method, plies may also be sorted within a buffer. In suchcase, the plies may be picked from a support of a buffer, and moved toanother support within that same buffer, or moved within the samesupport. This may e.g. be done to place a stack of plies correspondingto a set in a desired order.

Using the method, plies may also be removed from the buffer to besorted. In such case, the plies may also be picked from a support of abuffer, and moved to a support outside of the buffer, e.g. an externalsupport. In the sorting operation, plies may then be picked up fromsupports in the buffer and received by the external support to bestacked in a stack in a desired order. Such support outside of thebuffer may elegantly be located in a second buffer of the ply sortingdevice. Such buffer and second buffer may both be accessible by the samepicker. However, also a second picker may be provided together with thesecond buffer that can access the first buffer, e.g. in a cascadedarrangement of the device.

The cutout plies may be nested in the sheet to optimize the use of sheetmaterial. The completion of sets in the supports of the buffer may beused as a boundary condition in the nesting of the plies in the sheet.This way, during nesting, account may be taken of the available space atthe supports in the buffer. This allows for optimized use of availablebuffer space, and also allows processing time until completion of a setto be controlled or reduced. This feature may be seen as an invention initself, and may also be applied to ply sorting methods and devices inwhich the supports are not moved relative to each other.

As part of the step of picking a ply, a select group of gripper organsfrom a plurality of gripper organs arranged in a gripper plane on apicker may be actuated depending on the geometry of the ply to bepicked. Also, as part of the step of picking a ply, the occurrence ofdragging and/or trailing of material from a picker may be detected.

Further advantageous features of the invention are defined in thedependent claims. It should be noted that the technical features andsteps described above may each on its own be embodied in a ply pickingand sorting device, i.e. isolated from the context in which it isdescribed here, separate from other features or in combination with onlya number of features described in the context in which it is disclosedherein. Each of these features may further be combined with any otherfeature disclosed, in any combination.

The invention will be further elucidated on the basis of non-limitativeexemplary embodiments represented in the drawings. In the drawings:

FIG. 1 shows a schematic perspective view of a ply sorting deviceaccording to a first embodiment of the invention working in tandem witha cutter;

FIG. 2 shows a schematic top view of FIG. 1 ;

FIG. 3 shows a schematic perspective view of a gripper head of thepicker of the ply sorting device of FIG. 1 ;

FIG. 4 shows a schematic perspective view of the buffer of the plysorting device of FIG. 1 ;

FIG. 5 shows a schematic perspective impression of an array of supportsfor in the buffer of FIG. 4 ;

FIG. 6 shows a schematic side view of the buffer of FIG. 4 ;

FIG. 7 shows a schematic perspective view of a second embodiment of aply sorting device in accordance with the invention, and

FIG. 8 shows a schematic perspective view of a third embodiment of a plysorting device in accordance with the invention.

It should be noted that the figures are merely schematic representationsof preferred embodiments of invention. In the figures, identical orcorresponding parts are represented with the same reference numerals.

Referring to FIGS. 1-6 , a ply sorting device 1 according to a firstembodiment of the invention is discussed. The ply sorting device 1 worksin tandem with a cutter 2.

The material for the plies 3 is supplied as a sheet 4 of fiber material.The fiber material may be carbon fiber, but may also be or compriseother type of fiber material, e.g. glass fiber or aramid fiber. Thefiber material may have woven, or non-woven strands of fibers. Thestrands of fibers typically each have a single orientation. Preferably,the fibers in the material are parallel unidirectional, non woven fiberstrands. The fiber material may be impregnated with a resin. The resinmaterial may be thermosetting or thermoplastic material, and in thefinished product forms a matrix material. The resin may typically beuncured, e.g. in case of a thermosetting material. The resin may besticky, e.g. in case of uncured resin. The plies 3 in this example areunfinished products: they are to be placed in layers, and subjected toheat and pressure to form a product. Because they are unfinished, theplies 3 cut from the sheet 4 of resin impregnated material are delicate,and should be handled with care to prevent loss of integrity, and toprevent contamination. The impregnated fiber material may be providedwith a protective layer, e.g. a top or bottom backing that is to beremoved when the plies 3 are put in the mold. Sharp folding and exertionof (planar) force on the plies 3 is to be prevented. In order to ensurethis, the plies 3 are preferably picked, moved and stored in a planarorientation. Due to limited shelf life of the resin as unfinishedproduct, after cutting the plies 3 should be processed to productsfairly quickly. Also, prolonged storage of plies 3 or sets of plies 3 isbetter avoided.

Referring to FIGS. 1 and 2 , the sheet of material is typically providedon a roll, which is stored in a protective packaging. After removal ofthe packaging, the sheet 4 is unrolled from the roll at a roll supply 5,and is placed on a flat conveyor belt 6 of a cutter 2. The cutter 2typically is a numerically controlled X-Y knife, laser or jet cuttingmachine. The cutter 2 cuts plies 3 of different geometries. Plies 3 ofdifferent geometries may together make up a set to be used for moldingof a composite product. A set may typically comprise plies 3 ofdifferent size and shape, but may comprise or even consist of plies 3 ofthe same geometry. A composite product may itself be comprised ofseveral sets of plies 3. To optimize the use of the sheet material, acutting file is produced by nesting of the plies 3 of several sets.These sets may each be identical, but may also differ. For example,different sets corresponding to smaller and larger products may benested on the sheet 4 to optimize use of the sheet material. The outputof the cutter 2 is thus a sheet 4 with cutouts for plies 3, which istransported from the cutter 2 on a flat conveyor belt 6 to a pickupplane 7. In the example of FIG. 1 this is done by an unloading conveyor8 connected to a sorting conveyor 9 at the same level. In this case, theunloading conveyor 8 defines a flat pickup plane 7 in which the cutsheet 4 lies. The plies 3 may be picked as cutouts from the moving sheeton the sorting conveyor 9.

Due to the nesting, the plies 3 are typically not in an the order sothat subsequent plies 3 can be picked from the sheet 4 to form a set.For example, a ply 3 for a first set may come first, followed by anotherply 3 for a second set.

In order to accommodate for this, a ply sorting device 1 is provided.The ply sorting device 1 comprises a picker 10 and a buffer 11. In thisexample, the picker 10 is arranged to pick planar plies 3 of cut resinimpregnated fiber material and move them to the buffer 11 insubstantially planar orientation. The picker 10 is in the example ofFIG. 1 embodied as a robotic arm, carrying a gripper head 12. Instead ofa robotic arm, another type of moving device for the gripper head 12 maybe provided, e.g. a simple rail with a movable carriage for the gripperhead. Referring to FIG. 3 , the gripper head 12 of the picker 10 maycomprise a plurality of gripper organs 13 arranged in a gripper plane 14of the gripper head 12, e.g. suction cups. When picking a ply 3, aselect group of gripper organs 13 from the plurality of gripper organs13 arranged in the gripper plane 14 on the picker 10 is actuated by acontroller 15 depending on the geometry of the ply 3 to be picked. Whilepicking a ply 3, the occurrence of trailing of material from a picker 10may be detected. For this, a detection plane may be arranged parallel tothe pickup plane 7, e.g. a light screen, to detect any materialextending between the pickup plane 7 and the gripper plane 14.

Referring to FIGS. 4-6 , the buffer 11 comprises a plurality ofsubstantially planar supports 16 each arranged to receive plies 3 fromthe picker 10 and to support the plies 3 in planar orientation in astack.

Based on the data in the cutting file, the controller 15 arranges thatthe planar plies 3 of cut fiber material of differing geometries aresubsequently picked by the picker 10 and are each moved in substantiallyplanar orientation to a selected one of a plurality of supports 16 ofthe buffer 11. The controller 15 is in communication with the cutter 2and the sorting conveyor 9. The controller 15 can use the data of thecutting file to locate the various plies 3, and to select the supportwhere a set is collected to which the ply 3 is to be added. At thesupports 16, the plies 3 are received in a planar orientation to becomepart of a stacked set of plies 3. In accordance with the invention, thecompletion of sets in the supports 16 of the buffer 11 is used as aboundary condition in the nesting of the plies 3 in the sheet 4. Duringnesting, account is taken of the available space at the supports 16 inthe buffer 11. For example, if for all supports 16 plies 3 have beencut, and a set at particular support lacks one ply 3 to be completed,that ply 3 is included next in the nesting of the cutting file withpreference over another ply 3 with which a closer nesting may beachieved so that a support may be freed up sooner.

In accordance with an aspect of the invention, the planar supports 16are movably arranged relative to each other to receive the plies 3. Thesupports 16 can be moved from a storage position in which they have acovering arrangement that prevents receiving of plies 3, to a receivingposition that allows receiving of plies 3. Such a covering arrangementsaves space, and prevents contamination due to sheltering. By spacingthe supports 16 perpendicular to their plane, the covering arrangementmay be facilitated. In this embodiment, the supports 16 are arranged tobe movable perpendicular to their plane. The shelves 17 are embodied astrays, so that the plies 3 of the set may be supported in a protectedtrough. The shelves 17 are placed in a column, and are liftably mountedto a frame 18 transversely to the longitudinal direction of the shelves17. The shelves 17 are liftably mounted with a variable interspace S toaccommodate the picker 10 between shelves 17. As can be seen in FIG. 5and FIG. 6 , a lock 19 and a lifting table 20 may cooperate to provide aspacing between the shelves 17. The bottom shelf 21 in the spacing shownis in the receiving position, the other shelves 22 are covered and arein the storage position. The shelves of the column are thus arranged tobe moved relatively to each other in groups. Adjacent shelves of thecolumn can be parted, and provided with interspace to accommodate thegripper head of the picker between the shelves. By moving the shelves ofthe column up and down, the shelves that are to be parted can bepositioned at a fixed height before parting. All shelves can then bemade available for the picker to access at a single height position.

The column may be moved up or down to position the shelves to be partedusing the lifting table 20, e.g. by driving it with a spindle via asingle motor. When in position, an upper shelf of a set of shelves to beparted may be held by actuating a locking pin of the lock 19. Whensubsequently lowering the lifting table, an upper part of the columnremains in place, while a lower part of the column moves downward, andthe lower shelf 21 of the set of shelves that is on top of the lowerpart of the column is made accessible for the gripper head 12. This way,the lower shelf 21 of a set of shelves to be parted may be moved from astorage position in which it forms a support that is a coveringarrangement with a support formed by the upper shelf of the set thatprevents receiving of plies, to a receiving position that allowsreceiving of plies.

Referring again to FIG. 1 and FIG. 2 , one side 24 of the column ofshelves 17 of the buffer 11 facing the picker 10 is part of a stay outzone 23 that during operation is not accessible to humans. An oppositeside 25 of the column facing away from the picker 10 is part of a safezone 26 that during operation is accessible to humans. This way, thebuffer 11 may be implemented in a flexible production cell easilyaccessible to a robot, and yet be easily and safely accessible to humansas well. In particular, an operator may remove a set of plies 3 that iscompleted manually when the shelf is in the receiving position.

Referring to FIG. 7 , a second embodiment of the invention is shown.Here, the supports 16 of the buffer 11 are embodied as shelves 17 thatare each slidably mounted to a frame 18 transversely to a longitudinaldirection of the shelves 17. The shelves 17 are arranged in a column,and are vertically closely interspaced at fixed intervals. The shelves17 are arranged to slide outwards at opposing sides of the column from acovering arrangement that prevents receiving of plies 3, to a receivingposition that allows receiving of plies 3. In the covering arrangementthe shelf overlaps with other shelves 22, and in de receivingarrangement the shelf is substantially non-overlapping with the othershelves 22 and is free to receive plies 3. At a side 24 of the columnfacing the picker 10 the receiving position allows the picker 10 to dropplies 3 on the shelf 27; at a side 25 of the column facing away from thepicker 10 the receiving position allows an operator to take out the setof plies 3 when completed.

Referring to FIG. 8 , a third embodiment of the invention is shown.Here, the supports 16 are embodied as panels of different height, thatare slidable on tracks along the sorting conveyor 9. Each panel supportsa number of stacks of plies 3. When the stacks are completed to a set,the sets may be removed manually.

Thus a ply sorting device is disclosed, comprising a picker and abuffer, wherein the picker is arranged to pick planar plies of cut fibermaterial, in particular resin impregnated material, and move them to thebuffer, and wherein the buffer comprises a plurality of substantiallyplanar supports each arranged to receive plies from the picker and tosupport the plies in planar orientation, preferably in a stack, whereinthe planar supports are movably arranged relative to each other toreceive the plies.

Also, a method of sorting plies of differing geometry is disclosed, inparticular into sets, wherein planar plies of cut fiber material arepicked and moved to supports of a buffer where plies are received in aplanar orientation, in particular to become part of a stacked set ofplies, wherein supports are moved relative to each other to receive theplies.

The invention is not limited to the exemplary embodiment representedhere, but includes variations. For example, the buffer may be part of acabinet with a controlled environment, e.g. a freezer or light blockingcabinet to improve shelf life of pre-impregnated plies (prepregs)comprising thermosetting or thermoplastic matrix material.

Further, plies of cut fiber material may be manually picked and moved tosupports of a buffer, e.g. by an operator. This may be done in additionor as an alternative to the picker. The cut fiber materials may then beplaced manually into trays and/or onto shelves, for example intoremovable trays and/or onto shelves which have been removed from thebuffer. For instance, an operator may remove a tray or shelf from thebuffer and place cut plies into the tray or onto the shelf, andsubsequently load a stack of plies into the buffer with the tray orshelf. This way, cut plies may be manually picked and collected manuallyinto stacks on the trays and/or shelves, e.g. to manually form stacks ofidentical or similar plies, or to manually form stacks of plies thatform a set of plies that is not yet in the correct order for laying-up.A picker may then access the buffer of the ply sorting device to composestacks that correspond to sets, and may put plies in the set in thecorrect order for laying-up.

Also, in the ply sorting device a picker may be arranged to operatebetween buffers. This way a first buffer e.g. may be loaded manually byan operator and trays or plies may be picked from the first buffer bythe picker to moved to supports in a second buffer. This can be usefulto compose sets of plies, or to put sets of plies in the right order forlaying up.

Such variations shall be clear to the skilled person and are consideredto fall within the scope of the invention as defined in the appendedclaims.

LIST OF REFERENCE SIGNS

-   -   1. Ply sorting device    -   2. Cutter    -   3. Plies    -   4. Sheet    -   5. Roll supply    -   6. Conveyor belt    -   7. Pickup plane    -   8. Unloading conveyor    -   9. Sorting conveyor    -   10. Picker    -   11. Buffer    -   12. Gripper head    -   13. Gripper organs    -   14. Gripper plane    -   15. Controller    -   16. Supports    -   17. Shelves    -   18. Frame    -   19. Lock    -   20. Lifting table    -   21. Bottom shelf    -   22. Other shelves    -   23. Stay out zone    -   24. Side of stay out zone    -   25. Side of safe zone    -   26. Safe zone    -   27. Slidable shelf    -   S. Interspace

The invention claimed is:
 1. A ply sorting device, comprising a pickerand a buffer, wherein the picker is arranged to pick planar plies of cutfiber material and move them to the buffer, and wherein the buffercomprises a plurality of planar supports interspaced perpendicular totheir plane and wherein the supports are arranged to move perpendicularto their plane, each support being further arranged to receive pliesfrom the picker and to support the plies in planar orientation, whereinthe planar supports are arranged movable only perpendicular to theirplane relative to each other to receive the plies, wherein the supportsare arranged to be moved perpendicular to their plane from a storageposition in which they have a covering arrangement of a select supportthat prevents receiving of plies, to a receiving position with supportsabove the select support spaced perpendicular relative to the plane ofthe select support that allows receiving of plies by the select supportand wherein the select planar support assumes the receiving position byvertical movement of a group of the plurality of planar supports.
 2. Theply sorting device according to claim 1, wherein the supports areshelves.
 3. The ply sorting device according to claim 2, wherein theshelves are arranged above each other in a column.
 4. The ply sortingdevice according to claim 3, wherein the shelves are each slidablymounted to a frame transversely to a longitudinal direction of theshelves.
 5. The ply sorting device according to claim 2, wherein theshelves are liftably mounted to a frame transversely to a longitudinaldirection of the shelves.
 6. The ply sorting device according to claim5, wherein the shelves are liftably mounted with variable interspace toaccommodate the picker between shelves.
 7. The ply sorting deviceaccording to claim 1, further comprising a planar pickup planecomprising a moving belt surface associated with an output of a sheetcutter arranged to cut the planar plies from a sheet.
 8. The ply sortingdevice according to claim 7, wherein the picker comprises a plurality ofgripper organs arranged in a gripper plane.
 9. The ply sorting deviceaccording to claim 8, further comprising a detection plane arrangedparallel to the pickup plane, to detect material extending between thepickup plane and the gripper plane.
 10. The ply sorting device accordingto claim 1, operatively associated with a sheet cutter arranged to cutplies from a sheet.
 11. The ply sorting device according to claim 1,wherein one side of the buffer facing the picker is accessible and anopposite side of the buffer facing away from the picker is accessible.12. The ply sorting device according to claim 11, wherein the one sideof the buffer facing the picker is part of a stay out zone and whereinthe opposite side of the buffer facing away from the picker is part of asafe zone.
 13. A method of sorting plies of differing geometry,comprising, picking and moving planar plies of cut fiber material tosupports of a buffer where the plies are received in a planarorientation, and moving the supports only perpendicular to their planerelative to each other to receive the plies, wherein the supports aremoved from a storage position in which they have a covering arrangementof a select support that prevents receiving of plies, to a receivingposition with supports above the select support spaced perpendicularrelative to the plane of the select support that allows receiving ofplies by the select support and wherein the select planar supportassumes the receiving position by vertical movement of a group of theplurality of planar supports.
 14. The method according to claim 13,wherein the supports are moved apart in a lifting operation to receiveplies.
 15. The method according to claim 13, further comprising pickingthe plies as cutouts from a moving sheet.
 16. The method according toclaim 15, further comprising nesting the cutout plies in the sheet tooptimize the use of sheet material.
 17. The method according to claim16, further comprising using the completion of sets in the supports ofthe buffer as a boundary condition in the nesting of the plies in thesheet.
 18. The method according to claim 13, wherein as part of the stepof picking a ply, a select group of gripper organs from a plurality ofgripper organs arranged in a gripper plane on a picker is actuateddepending on the geometry of the ply to be picked.
 19. The methodaccording to claim 13, wherein as part of the step of picking a ply, theoccurrence of trailing of material from a picker is detected.
 20. Themethod according to claim 13 wherein the steps of picking and movingplanar piles are performed by a picker on one side of the buffer facingthe picker and the buffer is accessible on the one side of the bufferand on an opposite side of the buffer facing away from the picker. 21.The method according to claim 20 wherein the one side of the buffer ispart of a stay out zone and wherein the opposite side of the buffer ispart of a safe zone.
 22. A ply sorting device, comprising a picker and abuffer, wherein the picker is arranged to pick planar plies of cut fibermaterial and move them to the buffer, and wherein the buffer comprises aplurality of planar supports having a surface area greater than afootprint of a planar pile to be received on one of the plurality ofplanar supports, the planar supports being interspaced perpendicular totheir plane and wherein the supports are arranged to move perpendicularto their plane, each support being further arranged to receive pliesfrom the picker and to support the plies in planar orientation, whereinthe planar supports are arranged movable only perpendicular to theirplane relative to each other to receive the plies, wherein the supportsare arranged to be moved perpendicular to their plane from a storageposition in which they have a covering arrangement of a select supportthat prevents receiving of plies, to a receiving position with supportsabove the select support spaced perpendicular relative to the plane ofthe select support that allows receiving of plies by the select support.